Manufactured from chrome vanadium steel, hardened and tempered with a satin finish. Each socket has a knurled ring for extra grip. Supplied on a metal socket rail for secure storage. Display packed. Contents: 12 x Sockets: 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 22, 24mm Manufactured and tested generally in accordance with DIN3122 and ISO3315 Specifications